Absorption refrigerating system of the uniform pressure type



Dec. 5, 1950 c. A. MILLER 2,533,031

ABSORPTION REFRIGERATING SYSTEM OF THE UNIFORM PRESSURE TYPE Filed Dec. 8, 1947 2 Sheets-Sheet 1 1N VEN TOR.

Dec. 5, 1950 2,533,031

C. A. MILLER ABSORPTION REFRIGERATING SYSTEM OF THE UNIFORM PRESSURE TYPE Filed Dec. 8, 1947 2 Sheets-Sheet 2 IN V EN TOR.

Y Ma. 6

Patented Dec. 5, 1950 ABSORPTION REFRIGERATING SYSTEM OF THE UNIFORM PRESSURE TYPE Charles A. Miller, Evansville, Ind., assignor to Servel, Inc., New York, N. Y., a corporation of Delaware Application December 8, 1947, Serial No. 790,367

8 Claims.

I This invention relates to refrigeration and particularly to absorptionrefrigerating systems of the uniform pressure type. It is an object of this invention to provide an improved arrangement and location of several elements of a refrigerating system relative to a refrigerator cabinet.

In absorptionrefrigerating systems of the uniform pressure type wherein the interior or food storage space of the refrigerator cabinet is divided into a plurality of compartments cooled to different temperatures it is often desirable that the. freezing section of the evaporator be placed in an upperpart of the cabinet. This is particularly true when the freezing section comprises a relatively flat horizontal member which traverses substantially the entire width and depth of the interior of the cabinet and forms the bottom of a freezing compartment in the upper part of the cabinet. However, with uniform pressure absorption refrigerating systems wherein an inert gas storage or pressure vessel is used it is desirable that such pressure vessel be located at an elevation such that condensate formed therein will drain into an upper part of the evaporator. It is also desirable, and in fact necessary, that the pressure vessel be cooled in some manner so that refrigerant vapor conveyed thereto will be condensed therein.

Heretofore when it was desired that conden ate formed in the pressure vessel drain therefrom into the evaporator, the pressure vessel has been located in the flue at the rear of the cabinet at an elevation above the condenser. In gravity flow system, such location of the pressure vessel limits the height at which the condenser may be placed in the flue, which in turn limits the height at which the evaporator may be placed in the food storage compartment. The pressure vessel may be placed within the flue below the This may be accomplished by locating the drain conduit between the condenser and the evaporator in the flue. But here again the location of this drain in the flue obstructs passage of cooling air over the condenser.

In accordance with my invention, I provided an arrangement whereby the condenser is placed in the uppermost part of the flue so that a flat horizontal low-temperature evaporator'may be placed in a relatively high position in the food storage compartment of the refrigerator and still have a sufficient drop between the condenser and inlet of the evaporator for gravity flow of liquid refrigerant from the former to the latter. I also provide an arrangement whereby the pressure vessel, which in my case constitutes a horizontally elongated vessel, is placed in the upper part of a double wall insulated closure member, which closure member forms a portion of the rear wall of the refrigerator cabinet. The closure member is provided with the usual metal mounting plate, which mounting plate forms a part of the vertical flue at the rear of the refrigerator cabinet. The pressure vessel is arranged to receive uncondensed refrigerant vapor from the outlet of the condenser, and the pressure vessel is mounted in good thermal contact with the metal mounting plate, whereby refrigerant vapor conveyed to the pressure vessel is condensed therein, the condensate formed thereby is conveyed by gravity flow to the uppermost part of the evaporator and the heat of condensation is transmitted from the pressure vessel through the metal mounting plate to air flowing upward in the vertical flue without interfering with the passage of air over the condenser.

The conduit which conveys the liquid refrigerant from the condenser to the evaporator is also located within the closure member and a portion of this conduit is mounted in good thermal contact with the metal mounting plate, whereby liquid refrigerant passing from the condenser to the evaporator through this conduit is cooled by heat transfer from the conduit through the mounting plate to air flowing upward through the flue. Another portion of the conduit which conveys liquid refrigerant from the condenser to the evaporator is mounted in good thermal contact with the rich or cold gas side of a gas heat exchanger, which gas heat exchanger is also located within the double wall closure member.

With the above arrangement, the condenser is .so mounted in the flue that liquid refrigerant flows therefrom into a low-temperature section of the evaporator which section is located at a relatively high level in the food storage compartment of the refrigerator, the pressure vessel is arranged below the condenser in a manner that heat is transferred from the pressure vessel to air passing through the flue without interfering w th the peeling of the condenser, while at the :chamber 14. suitable means, as by a gas burner :19 arranged end of an analyzer 23.

same time discharging condensate from the pressure vessel to the evaporator, and liquid refrigerant conveyed from the condenser to the evaporator is precooled without interfering with the passage of cooling air over the condenser.

The invention together with the above and other objectsv and advantages will be more clearly understoodfrom the following detailed description, taken in connection with the accompanying drawings, wherein:

Fig. l is a view diagrammatically illustratinga refrigerating system incorporating my invention.

Fig. 2 is a side elevational view, partly in section, of a refrigerator incorporating my invention.

Fig. 3 is a front elevational view of the upper half of the refrigerator shown in Fig. 2.

Fig. i is a transverse sectional view taken on line 4 of Fig. 2.

Fig. 5 is a rear elevational view looking in the direction of the arrows 5-5 in Fig. 2.

Referrin to :Fig. l, for'purposesgof illustration, I have incorporated my invention in auniform :pressure absorption refrigerating system .ofnthe gravity flow type, which system includes :generally, a :generator W, a condenser than evaporator t2, an absorber 1'3 and :conduits 'in- :terconnecting said elements forrflow 'of arefrigcrating medium, .an absorption "liquid and a pressure-equalizing gas. for-example, a solution of refrigerant inabsorp The system contains,

tionliquid, such as ammonia in water, and an vauxiliary inert gas, such as hydrogen.

dome l 'i. A-ri-ser orvapor-lift conduit i8 is con- -nected 'from chamber 'M to .the .upper part .of standpipe E6.

The lower end ofconduit i8 extends downward through the dome I! :into The generator is heated by any so that the flame therefrom is projected into the lowerend of a flue which extends concentrically through the shell of the generator. The upper end of standpipe HE is connected by a vent conduit 2! and a conduit 22"to the lower The upper end of the analyzer i connected by a conduit .24 to the pper or inlet end of condenser H. The outlet end of the condenser 'is connected by a conduit '25 to =a freezing section [2 of the-evaporator I2. Chamber P5 of the generator is connected by a-conduit 25, a lower portion of vent conduit .2 i, an inner passage 2'! of a liquid heat exchanger 28 and a conduit 29 to the upper part of absorber I 3. As shown, conduit 26 passes through the analyzer '23. The lower end of the absorber -is-connected to chamber M of the generator by an absorber vessel 30, a conduit 31 forming the outer passage of liquid heat exchanger 28, a conduit 32, analyzer 23 and a conduit 33.

The upper part of theabsorber i3 is connected bya'conduitfi i, an outer passage 35 of an auxiliary gas heat exchanger 36, a conduit 37, an inner .passage 38 of main .gas heat exchanger 39, and a conduit ill to the inert gas inlet end :of freezing section lz of'the evaporator. The

exchanger, a conduit :43 which forms the inner the next lower section I3 of the absorber.

passage of the auxiliary gas heat exchanger 36, a conduit 44, and absorber vessel 30 to the lower part of absorber [3. Auxiliary gas heat exchanger 36 is provided at its lower end with a liquid trap 45 for conveying liquid from the outer passage 35 of this heat exchanger into conduit-.44.

As shown, absorber I3 includes an upper section 13 into one end of which section conduit 29 is connected and at the opposite end of which section a conduit 46 connects with A pressure vessel 41 i connected at one end to conduit 25 by a conduit 48, and at its opposite end the pressure vessel is connected by a conduit 49 to the outer passage 42 of gas heat exchanger '39.

Referring now to Figs. 2 and 5 of the drawings, in accordance with my invention, the condenser H includes two horizontal rows of tubes provided with lheattransfer fins H and fitted :into ithezupper portion of a vertical flue D at the rear of the refrigerator. A metal ,mounting plate 59 forms the outer wall of a double wall :insulate'd closure member 5!, which closure .m-ember forms a part of the rear wall of the refrigerator, and which mounting plate forms a part of the'vertical'flue. Pressure vessel '41 is mounted in the upper portion of the closure member 5i and is welded along its length to mounting .platefifl, as at "M Conduit 25 which delivers refrigerant from the condenser to the freezing section (12 of :the evaporator is welded, as at 25 to:the:mountingplate:5i3, and,.as

at.:25 ?,ato the outer surface of'main liquid'heat'exchanger 39. Closure member 5! is provided with suitable .insulation, not shown. Only so 'much of :the refrigerating system as is necessary fora complete understanding of my invention :has been shown in Figs. 2 and 5.

As shown in Figs. 2 and 3, the freezing section E2 and the boxicooling section l2 of the evaporator are so arranged within the refrigerator cabinet as to provide an ice freezing :compartment A, a low-temperature or frozen food compartment B and a food storage compartfrigerator and is provided at its front with a hinged door '53.

The arrangement is such that both the ice freezing compartment A and the low-temperature compartment B are insulated from the food-storage compartment C. A gasket, notshown, may be placed between the door 53 of thelow-temperature compartment and the door E of the refrigerator to further insulate compartment A from compartment: C.

In operationheat applied to the flue -20 of the generator causes expulsion of ammonia vapor out of solution. The vapor expelled from solution in chamber 14 accumulates in dome I! and rises through conduit ificausing upward flow of liquid through this conduit by vapor liquid-lift action into the upper end of standpipe Iii. The vapor flows from the upper end of :the standpipe absorption solution conduit 3 through conduits 2| and 22 into and upwardly through the analyzer 23, and from there the vap r flows through conduit 24 into the condenser H.

ter-current relation in this section of the evaporator, whereby the liquid evaporates and diffuses into the inert gas with consequent absorption of heat from the evaporator and its surroundings, that is, from ice trays, for example, that are positioned upon the flat upper surface of this evaporator section and from the low-temperature compartment B below this evaporator section.

The mixture of inert gas and refrigerant vapor flows from section [2 of the evaporator through conduit ill into section l2 of the evaporator wherein this mixture of gas and refrigerant vapor flows in concurrent relation with liquid refriger ant that flows from section 12 into section i2 through a conduit 52. In section l2 of the evaporator liquid refrigerant evaporates and diffuses into the partially enriched inert gas, thereby cooling food storage compartment C, and the enriched inert gas passes from this section of the evaporator through conduit ii, outer passage t2 of the main heat exchanger, conduit :3, conduit 44 and absorber vessel 39 into the lower end of absorber l3.

In the absorber, the rich mixture of inert gas and refrigerant vapor is brought in contact with that flows into the upper part of the absorber through conduit 28. The absorption solution flows from conduit 2& downward through section E3 of the absorber thereby tending to push the inert gas toward conduit 3%, whereby the how of inert gas is started and continned in the proper direction, and the absorption liquid is conveyed from conduit ifi through conduit it into the next lower conduit 33* of the absorber. From there, the absorption liquid flows downward in the remainder of the absorber in counter-current relation to rich mixture of inert gas and refrigerant vapor flowing upward through that part of the absorber, whereby refrigerant vapor is absorbed into the absorption solution and the impoverished inert gas passes through outer passage 35 of gas heat exchanger 33, conduit 37, inner passage 33 of the main gas heat exchanger, and conduit to, back to the low-temperature section i2 of the evaporator.

Absorption solution rich in refrigerant vapor flows from the lower portion of the absorber into absorber vessel 30 and from there, the enriched absorption solution flows through conduit 3 l conduit 32, analyzer 23, and conduit 33 into chamber It. of the generator. In the generator refrigerant vapor is expelled from solution in chainbers M and i5 and in standpipe l6. Refrigerant vapor expelled from solution in chamber hi passes upward through vapor-lift conduit i8, as explained above, and the refrigerant vapor expelled from solution in chamber i5 and standpipe I6 passes upward through solution in the standpipe to the upper portion thereof from whence the vapor passes to the condenser, as explained above. The absorption solution weak in refrigerant is conveyed from chamber i5 through conduit 26, the lower part of conduit 2|, conduit 2'], and conduit 29 to the upper part of the absorber. The arrangement shown particularly in Figs. 2

Inert gas flows Lil) and 5 of the drawings is such that heat is trans ferred from the pressure vessel 4i! and from a portion of conduit 25 through mounting plate 50 to air flowing upward through flue D. With this arrangement the pressure vessel andthe conduit which conveys liquid refrigerant from the condenser to the low-temperature section of the evaporator may be placed Within the closure member 5! so as not to obstruct the flow of air through flue D, while at the same time transferring heat from the pressure vessel and from conduit 25 to cooling air flowing upward in the flue. The liquid refrigerant is precooled further by placing a portion of conduit 25 in good thermal contact with the rich or cold side of gas heat exchanger 39.

While I haveillustrated and described but one embodiment of my invention, the invention obviously may take other forms and be variously applied'within the scope of the following claims.

What is claimed is: 1. In a refrigerator, a refrigerator cabinet including a food storage compartment, 9, flue at the rear of said compartment and an insulated closure member therebetween, and a refrigerating apparatus for cooling said food storage compartment, said refrigerating apparatus including a condenser within said flue and having a refrigerant vapor inlet and a refrigerant vapor and liquid refrigerant outlet, a pressure vessel within said closure member, an evaporator within said food storage compartment and having a liquid refrigerant inlet, conduits interconnecting said elements for flow of liquid refrigerant from the condenser to the evaporator, refrigerant vapor from the condenser to the pressure vessel and liquid refrigerant from the pressure vessel to the evaporator, and means including a portion of said closure member for cooling said pressure vessel, said pressure vessel being positioned within said closure member at an elevation below the level of the vapor and liquid refrigerant outlet of said condenser and above the level of the liquid refrigerant inlet of said evaporator, whereby condensate formed in the pressure vessel flows therefrom into the evaporator.

2. In a refrigerator, a refrigerator cabinet ineluding a food storage compartment, a due at the rear of said compartment and an insulated closure member between said compartment and said flue, and a refrigerating apparatus for cool ing said food storage compartment, said. refrigerating apparatus including a condenser within an upper portion of said fiue, a pressure vessel within said closure member, an evaporator with- 'tor, refrigerant vapor from the condenser to the pressure vessel and liquid refrigerant from the pressure vessel to the evaporator and means including a portion of said closure member for transferring heat from said pressure vessel to air flowing through said flue, said pressure vessel being positioned within said closure member at an elevation below the level of said condenser and above the level of said evaporator, the construction and arrangement being such that re frigerant vapor conveyed to the pressure vessel is'condensed therein, the heat of such condensation is transferred to air flowing through. the flue and the" condensate formed in the pressure ves- 4 sel is conveyed to the evaporator.

the'rear-of said compartment and-a double wall closure member between said compartment and said flue, said double wall closure member including a metal plate which forms a part of said flue, and a refrigerating apparatus for cooling said food storage compartment, said refrigerating apparatus including a condenser in the upper portion of said flue, a pressure vessel within saidclosure member, an evaporator with- .insaid food storage compartment and conduits interconnecting said elements for flow of liquid refrigerant from the condenser to the evaporator, refrigerant vapor from the condenser to the pressure vessel and liquid refrigerant from .the pressure vessel to the evaporator, said pressure vessel being positioned within said closure member ,at an elevation below the level of the lowermost part of said condenser and above the level of the uppermost part of said evaporator and in thermal contact with the metal plate of said closure member, the construction and arrangement-being such that refrigerant vapor conveyed to the pressure vessel is condensed therein, the heat of condensation is transferred through the metal plate to air flowing through the hue and the condensate formed in the pressure vessel is conveyed to the evaporator.

4. In a refrigerator, a refrigerator cabinet including a food storage compartment, a flue at the rear ofsaid compartment and a double wall closure member therebetweemsaid double wall closure member including a metal plate which forms a part of said flue, and a-refrigerating apparatus for cooling said food storage compartment, said refrigerating apparatus including .a condenser within an upper portion of said flue, a

pressure vessel within said closure member, .an

evaporator within said food storage compartment, a first conduit connecting said condenser andisaid evaporator for flow of liquid refrigerant from the former to the latter and a second conduit connecting said first conduit and said pressure vessel for flow of refrigerant vapor to the pressure vessel and for flow of liquid refrigerant from the pressure vessel to said first conduit, said pressure vessel being arranged in said closure member below the level of said condenser and above the level of saidevaporator and in thermal contact with the metal plate of said closure member, the construction and arrangement being such that refrigerant vapor conveyed to the pressure vessel is condensed therein, the heat of such condensation is transferred through the metal plate to air flowing through the flue and the condensate formed in the pressure vessel is conveyed to the evaporator.

5. In a refrigerator, a refrigerator cabinet including a food storage compartment, a vertical flueat the rear of said food storage compartment and a double wall closure member between said food storage compartment and said vertical flue, and a refrigerating apparatus for cooling said food storage compartment, said refrigerating apparatus including a condenser located in the 'upper portion of said flue, a pressure vessel loflue at'the rear of said'food storage compartment :and a double wall :closure member between said food storage compartment and :said vertical-flue, and a refrigerating apparatus for cooling said food storage compartment, "said refrigerating Tapparatus including a condenser located in the upper portion of said flue, a pressure vessel and a gas heat exchanger located within said closure member, an'evaporator located in said food storage compartment and a conduit leadingfrom an outlet of said condenser to an inlet 'of said evaporator, said conduit having a portion thereof in thermal contact with one of the walls :of said closure member and another portion thereof :in thermalcontact with said gas heat exchanger.

7. Ina refrigerator, refrigerator cabinet including a food storage compartment, 3, vertical flue at the rear of said food storage compartment and a double wall closure member between -said food storage compartment and said vertical flue, and :a refrigerating apparatus for cooling said food storage compartment, said refrigerating-apparatus including a condenser located *in the upper portion of said iiue, a pressure vessel and a gas heat exchanger located within said closure member, an evaporator located in'said food-stol age compartment and a-oonduit leading from an outlet of said condenser to an inlet of said evaporator, said conduit having a portion thereof in iermal contact with one of the walls of said closure member and another portion thereof in thermal contact with said gas heat exchanger, said pressure vessel comprising a horizontally elongated member arranged in thermal contact with the one wall of said closure member.

8. .In a refrigerator, a refrigerator cabinet including a food storage compartment, a vertical due at the rear of said food storage compartment and a double wall closure member between food storage compartment anclsaid vertical fine, and a refrigerating apparatus for cooling said food storage compartment, said refrigcrating apparatus including a condenser located in the upper portion of said flue, apressure vessel and a gas heat exchanger located Within said closure member, an evaporator located within said food storage compartment, a first conduit leading froman outlet of :said condenser to an inlet 'ofisaid evaporator, said first conduit having a portion thereof arranged in thermal contact with one of the walls of said closure member and another portion thereof in thermal contact with said gas heat exchanger, said pressure vessel comprising a horizontally elongated member arranged in thermal contact with the said one wall of the closure member and positioned at an elevation below the level of theoutlet of the condenser and above the level of the inlet of the evaporator, a second conduit con-- necting said pressure vessel to *said firstconduit and a third conduit connecting-said pressure vessel to the gas heat exchanger, substantially the entire lengthof each of said conduits being within said closure member.

CHARLES A. Mill-ER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,063,292 Bergholm Dec. 8, 1936 2,211,713 Bergholm Aug. 13, 1940 2,345,453 Brace Mar. 28, .1944 2,345,505 Siedle Mar. 28, 1944 2,377,051 :Sutton :May.29., I945 

